what are meta tags?

meta tags are labeled as meta keyword tags and meta descriptions tags. These tags are invisible to the user and are used to supply data or directions to the search engines in order to access information.

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What is Anchor Text?

It is the visible text that is hyper linked to another page ?

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What does the 301 server response code signify?

Moved Permanently

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how get a list of all pages indexed by google?

You can do site:example.com searches with  results per page, but if you
 try to do so with a script, then you will be stopped after just a few requests.

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Security issue for sitemap SEO?

They typically name their sitemap something like sitemapRXTNAP.xml and submit it to Google using webmaster tools, rather than listing it in robots.txt

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how access a method in the parent class that's been overridden in the child?

Prefix parent:: to the method name:

class shape {
    function draw( ) {
        // write to screen
    }
}

class circle extends shape {
   function draw($origin, $radius) {
      // validate data
      if ($radius > 0) {
          parent::draw( );
          return true;
      }

      return false;
   }
}

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how execute different code depending on the number and type of arguments passed to a method?

PHP doesn't support method polymorphism as a built-in feature. However, you can emulate it using various type-checking functions. The following combine( ) function uses is_numeric(), is_string(), is_array(), and is_bool():

// combine() adds numbers, concatenates strings, merges arrays,
// and ANDs bitwise and boolean arguments
function combine($a, $b) {
    if (is_numeric($a) && is_numeric($b)) {
        return $a + $b;
    }

    if (is_string($a)  && is_string($b))  {
        return "$a$b";
    }

    if (is_array($a)   && is_array($b))   {
        return array_merge($a, $b);
    }

    if (is_bool($a)    && is_bool($b))    {
        return $a & $b;
    }

    return false;
}

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want to link two objects, so when you update one, you also update the other?

Use =& to assign one object to another by reference:

$adam = new user;
$dave =& $adam;

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how eliminate an object?

Objects are automatically destroyed when a script terminates. To force the destruction of an object, use unset( ):

$car = new car; // buy new car
...
unset($car);    // car wreck

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how create a new instance of an object?

Define the class, then use new to create an instance of the class:

class user {
    function load_info($username) {
       // load profile from database
    }
}

$user = new user;
$user->load_info($_REQUEST['username']);

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